Centrifugal force has long been used as an aid in the casting of materials, especially metals. In its earliest forms, centrifugal casting was used simply to ensure that the mold was completely filled with liquid metal. More recently, centrifugal casting has been used to form composite materials. In particular, it has been used to infiltrate ceramic reinforcements with a liquid metal. For many popular metal/ceramic systems (e.g., metals such as aluminum, zinc, magnesium, titanium, iron (steel), copper, nickel, superalloys, and alloys based on these metals, combined with reinforcements such as carbon (e.g., as graphite), silicon carbide, alumina, silica, titanium carbide, titanium boride, and mixtures thereof), the liquid metal does not “wet” the ceramic, so some force must be used to introduce the metal into a reinforcement preform. For example, see U.S. Pat. No. 5,002,115, incorporated by reference herein, which describes the use of a spinning mold to force molten aluminum or zinc into a silicon carbide preform.
Taha, et al., “Metal-matrix composites fabricated by pressure-assisted infiltration of loose ceramic powder,” J. Mat. Proc. Tech. 73:139-146 (1998) compares centrifugal casting and squeeze casting of Al-12Si-2Mg/Al2O3 composites, and finds significant advantages to centrifugal casting. In particular, the pressure necessary to infiltrate the preform in centrifugal casting was found to be significantly lower than the required pressure for squeeze casting.